From Wood and Kienle (1990) [1]: "Segula volcano is built upon a 100-m-deep marine platform by the accumulation of flows and pyroclastic material emanating from a single center. Although there are no dated eruptions, some flows and pyroclastic deposits are so little weathered that ages of only a few hundred years are estimated. Pyroclastic material covers much of the cone's surface and a cinder cone resides in the middle of the summit crater."